Preview video calls with Knock Knock

When you call someone using Duo, the other person can see live video of you while the phone rings if they have you as a contact. You won't be able to see the person you're calling until they answer.

You’ll also only see video from callers you have as contacts.

To turn Knock Knock on

  1. Open Duo.
  2. In the top right corner, tap More More and then Settings and then Knock Knock.
  3. Turn Knock Knock on.

Can't see video preview for incoming call

If you can't see a video preview when someone calls you, the other caller has Knock Knock turned off or they're not in your contacts.

Note: If you’re on an iPhone, you’ll need to see the video preview through the call notification. When you get the notification for an incoming call:

  • If your phone is locked: Swipe left on the notification and tap View and then Preview.
  • If your phone is unlocked: Swipe down on the notification and tap Preview.
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Caroline is a Google Duo expert and author of this help page. Help her improve this article by leaving feedback below.

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